I've got something called "automatic headlamp control*" in my 2002 X.

In the manual it says : When the switch is set to this position the system automatically activates or deactivates the low beams in response to changes in ambient light (in tunnels, at dusk, etc.) as well as in rain and snow. (page 100 in the 3.0 manual)

And that you can have the sensitivity of this function adjusted.

Is this what you're talking about?

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